The iPhone 5s comes with Apple's new Touch ID sensor, which can scan your fingerprint and compare it to the fingerprint that you have stored in the phone to decide if you're the owner of the device and whether or not the device's Lock Screen should let you in.

Whenever your fingerprint fails to register, not only will the iPhone 5s not let you past the Lock Screen, but the slide to unlock text changes to say, "try again." A new free jailbreak tweak called Custom Touch ID Fail by iOS developer Charlie Riesner is now available in Cydia that lets you change that text to whatever you want.

As shown above, when the Touch ID sensor fails to see a match between our fingerprint and the fingerprint(s) we have on file, the tweak displays the text "FLOP" instead of "try again." The tweak adds a preferences pane to the Settings application where you can configure the custom text you want to appear, and where you can enable or disable the tweak on demand:

Maybe... just maybe... you can now convince someone that your iPhone 5s is about to self destruct when they get the fingerprint wrong. Unless, of course, you can think of something funnier to put there when the fingerprint doesn't register.

If you want to give Custom Touch ID Fail a try, it's available for free in Cydia's BigBoss repository right now. iOS 7 and a Touch ID-enabeld device are required to use this tweak.